1. Field of the Invention
The invention is directed generally to a chemical feeder for providing a sanitizing chemical to water and more particularly to a chemical feeder which automatically provides controlled amounts of a sanitizing chemical to water in a circulating system.
2. Description of Related Prior Art
A number of chemical feeders are disclosed in the prior art. Thus, U.S. Pat. No. 4,210,624 discloses a module which is attached to the upper end of a water filter assembly. Water supplied to body 19 through inlet port 39 rises to an unknown level within body 19 and wets an unknown amount of chlorine pellets in the body. It is difficult to accurately control the amount of chlorine supplied to the water in this arrangement because the water level in the module is unknown as is the number of chlorine pellets which will be contacted by the water.
U.S. Pat. No. 3,899,425 discloses an on-line chemical feeder 80 which is attached to a modular filter assembly for water. The feeder utilizes chlorine tablets 98 as the source of chlorine and water flows through the filter into the feeder and wets an unknown number of the tablets in pipe 82 which makes it difficult to control the amount of chlorine supplied to the water.
U.S. Pat. No. 3,383,178 discloses a chemical feeder for supplying chlorine to water but this device involves a relatively complicated arrangement for controlling the flow rate of the water. Hence, the amount of chlorine supplied to the water cannot be accurately controlled.
A commercial swimming pool water chlorinator is described in the brochure entitled "Olin PULSAR.RTM. Pool Feeder System". This chlorinator has the disadvantage that it is difficult to control the amount of chlorine supplied to the swimming pool water because of the cyclical operation of the accumulator and plugging of the orifices in the chemical grid. Additionally, the chlorinator described in this brochure requires adjusting the position of the chemical container to change the amount of chlorine supplied to the swimming pool water.
Another commercially available chlorinator is described in the brochure entitled "PULSAR.RTM. II Commercial Pool Feeder". In this chlorinator, it is difficult to accurately control the amount of chlorine supplied to the swimming pool water because of the cyclical operation of the siphon.
Another commercial chlorinator is described in a brochure entitled "S-2 Automatic Chlorine Feeder For In-Ground Pools". The chlorinator described in this brochure has a constant water level and a constant water flow rate and adjusts the chlorine feed to the swimming pool water by changing the position of the "S-2 Feeder Pac" to vary the level of submergence of the chlorine pellets in the "Feeder Pac". It is difficult to accurately control and maintain the chlorine feed to the swimming pool water with this device.